Patent No. ZL200720004154.3 Chinese utility model patents, disclosed a closure detector, which mainly solve the defects existed in previous closure detector, such as large size, poor aseismicity and low security.
However, for closure detector disclosed by this patent, contact or disengagement between the fixed contact and movable contact was achieved through two sets of movable contacts, two sets of fixed contacts, rocker slot, nail, slider and other structures. The overall structure of this closure detector is extremely complicated, so the disclosure of this patent has little contribution for further reducing the size of the closure detector. Otherwise, for the complex structure equipment, you must spend high cost on manufacturing, installation and routine maintenance.